The Chilean international is out of contract at the end of the season and was also a target for Manchester City, but United appear to have stolen a march on their local rivals.

"I worked on transfers for 30 years so it is likely to happen, but at any moment it can break down ... If it doesn't happen, he will play on Saturday." Wenger told a news conference, adding that United midfielder Henrikh Mkhitaryan could move in the other direction.

"I like the player. We played many times against him when he was at (Borussia) Dortmund. He appreciated the quality of our games ... The wages would not be a problem," Wenger added.

"This would be an exchange of players and I think one would replace the other," Wenger said, adding that he would still be in the market for more recruits.

Arsenal sold England international Theo Walcott to Premier League rivals Everton on Wednesday.

Armenia international Mkhitaryan has faded this season and has fallen down the pecking order under manager Jose Mourinho, who omitted the 28-year-old from United's squad for their 3-0 win over Stoke City on Monday.

City this week pulled out of the race to sign Sanchez after deciding that the player's wage and transfer fee demands were too high but United appear to have no such concerns.

British media reports say that United are prepared to pay the striker more than 350,000 pounds ($485,000) per week.

"I wouldn't like to come out on the numbers because that's Man United's problem," Wenger said. "I respect Man United because they generate the money they pay to the players with their own resources, so you have to respect that.

"He's 29 years old so the next contract will be, of course, very important for him. ($1 = 0.7217 pounds) (Reporting by Simon Jennings and Aditi Prakash in Bengaluru; Editing by Kevin Liffey and Keith Weir)